Wollaston Prism

A Wollaston prism consists of two right triangle prisms (commonly made of calcite or quartz) cemented together. When the beam passes through the interface, the prism produces two orthogonal linearly polarized divergent beams, the ordinary ray (o ray) and extraordinary ray (e ray). The beams diverge from the prism, giving two polarized rays; their divergence depends on the wedge angle of the prisms.